Method and Device for Notifying Channel Occupation Time, and Base Station and User Equipment

ABSTRACT

A method and a device for notifying channel occupation time, a base station and a user equipment. The method which applies to a base station includes: in an unlicensed spectrum, performing LBT and channel access; and when a channel is accessed successfully, sending a time slot format information which indicates one or more time slots of one or more cells to a UE through a PDCCH. The method which applies to a user equipment includes: in an unlicensed spectrum, receiving time slot format information, sent by a base station via a PDCCH after channel access is successfully completed, indicating one or more time slots of one or more cells; acquiring channel occupation information and channel release information according to the time slot format information; and according to the channel occupation information and the channel release information, performing downlink reception, uplink transmission or channel access in symbols of each time slot.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation Application of the U.S. patentapplication Ser. No. 16/969,544 filed on Aug. 12, 2020, which is thenational phase of International Application No. PCT/CN2019/080926, filedon Apr. 2, 2019, which claims priority to Chinese Patent Application No.201810290152.8, filed on Apr. 3, 2018, and entitled “METHOD AND DEVICEFOR NOTIFYING CHANNEL OCCUPATION TIME, AND BASE STATION AND USEREQUIPMENT”, the entire disclosure of which is incorporated herein.

TECHNICAL FIELD

The present disclosure generally relates to wireless communicationtechnology field, and more particularly, to a method and a device fornotifying channel occupation time, a base station and a user equipment.

BACKGROUND

In a 3rd Generation Partnership Project (3GPP) New Radio (NR) system, aradio frame with a time domain length of 10 ms is divided into 10subframes with a same length of 1 ms, and each subframe may includemultiple time slots according to according to different subcarrierintervals. Each time slot includes a certain number of symbols, and anumber of symbols is determined by Cyclic Prefix (CP) type. Comparedwith a Long Term Evolution (LTE) special subframe structure which has afixed 10 types of downlink, Guard Period (GP) and uplink symbols, SlotFormat (SF) is introduced in a NR system, wherein each time slotincludes a certain number of downlink, flexible (denoted by ‘X’) anduplink symbols. The SF may be configured in three ways: semi-staticcell-level Radio Resource Control (RRC) signaling configuration; UserEquipment (UE) specific RRC signaling configuration; and dynamicallysending Slot Format Indication (SFI) to a group of UEs through PhysicalDownlink Control Channel (PDCCH), that is, dynamic slot formatinformation. The SFI information carried on the PDCCH may indicateformat of one or more time slots on one or more carriers. After the SFIis detected, the UE obtains an index information and the indexinformation points to a UE-specific table. The UE specific table tellswhich symbols in the time slot are uplink (UL), which symbols aredownlink (DL), and which symbols are “flexible”. The UE-specific tableis configured and combined in a single-slot-format table. Thesingle-slot-format table includes all time slot formats (less than 256)supported in NR. It has been determined that time slot format in thesingle-slot-format table (as shown in Table 1) includes at most twodownlink/uplink (D/U) switching points in each time slot.

TABLE 1 for- symbol number in a time slot mat 0 1 2 3 4 5 6 7 8 9 10 1112 13 0 D D D D D D D D D D D D D D 1 U U U U U U U U U U U U U U 2 X XX X X X X X X X X X X X 3 D D D D D D D D D D D D D X 4 D D D D D D D DD D D D X X 5 D D D D D D D D D D D X X X 6 D D D D D D D D D D X X X X7 D D D D D D D D D X X X X X 8 X X X X X X X X X X X X X U 9 X X X X XX X X X X X X U U 10 X U U U U U U U U U U U U U 11 X X U U U U U U U UU U U U 12 X X X U U U U U U U U U U U 13 X X X X U U U U U U U U U U 14X X X X X U U U U U U U U U 15 X X X X X X U U U U U U U U 16 D X X X XX X X X X X X X X 17 D D X X X X X X X X X X X X 18 D D D X X X X X X XX X X X 19 D X X X X X X X X X X X X U 20 D D X X X X X X X X X X X U 21D D D X X X X X X X X X X U 22 D X X X X X X X X X X X U U 23 D D X X XX X X X X X X U U 24 D D D X X X X X X X X X U U 25 D X X X X X X X X XX U U U 26 D D X X X X X X X X X U U U 27 D D D X X X X X X X X U U U 28D D D D D D D D D D D D X U 29 D D D D D D D D D D D X X U 30 D D D D DD D D D D X X X U 31 D D D D D D D D D D D X U U 32 D D D D D D D D D DX X U U 33 D D D D D D D D D X X X U U 34 D X U U U U U U U U U U U U 35D D X U U U U U U U U U U U 36 D D D X U U U U U U U U U U 37 D X X U UU U U U U U U U U 38 D D X X U U U U U U U U U U 39 D D D X X U U U U UU U U U 40 D X X X U U U U U U U U U U 41 D D X X X U U U U U U U U U 42D D D X X X U U U U U U U U 43 D D D D D D D D D X X X X U 44 D D D D DD X X X X X X U U 45 D D D D D D X X U U U U U U 46 D D D D D X U D D DD D X U 47 D D X U U U U D D X U U U U 48 D X U U U U U D X U U U U U 49D D D D X X U D D D D X X U 50 D D X X U U U D D X X U U U 51 D X X U UU U D X X U U U U 52 D X X X X X U D X X X X X U 53 D D X X X X U D D XX X X U 54 X X X X X X X D D D D D D D 55 D D X X X U U U D D D D D D56- Reserved 255

Details are described as follows.

1. There is no switching point in a time slot: 14 downlink symbols (asshown in FIG. 1 ), or 14 Unknown symbols (as shown in FIG. 3 ), or 14uplink symbols (as shown in FIG. 2 ).

2. There is one D/U switching point in a time slot (as shown in FIG. 4): a time slot starts with zero or more DL symbols and ends with zero ormore UL symbols, with Unknown symbols in the middle which has at leastone Unknown symbol, and at least one DL symbol or at least one ULsymbol.

3. There is two D/U switching points in a time slot (as shown in FIG. 5): first seven symbols of the time slot start with zero or more DLsymbols and end with at least one UL symbol in Symbol 6, the middle ofwhich is Unknown symbols; and last seven symbols start with zero or moreDL symbols, end with zero or more UL symbols, and has zero or moreUnknown symbols in the middle.

3GPP standards organizations are researching on how to deploy NRnetworks on unlicensed spectrum, so as to achieve purposes of fair andeffective use of unlicensed spectrum and improve data transmission ratein a NR system. There are three ways to use unlicensed spectrum in a NRsystem: first, a NR cell in an unlicensed spectrum is used as a primarycell; second, a UE accesses a NR cell in an unlicensed spectrum througha LTE cell; and third, a UE accesses a NR cell in an unlicensed spectrumthrough a NR cell. In the last two ways, licensed spectrum andunlicensed spectrum can be combined in a way that is similar to carrieraggregation, that is, a UE and a gNB (which means a 5G base station) maywork in both licensed spectrum and unlicensed spectrum.

In a 3GPP LTE system, a Listen-Before-Talk (LBT) process is used toachieve coexistence of Licensed Assisted Access (LAA) of differentoperators and other systems in unlicensed spectrum. In the LBT process,nodes in the unlicensed spectrum determines whether a current channel isavailable or not before data transmission through Clear ChannelAssessment (CCA). Thus energy detection is used to determine whether thechannel is occupied or not in any LBT process. Some regional regulationsstipulate an energy detection threshold. If energy received by a node ishigher than this threshold, the channel is considered as busy. There aretwo channel access processes supported in LTE License Assisted Access(LAA) downlink transmission: a channel access process (that is alsocalled Cat 4 channel access) that needs to send Physical Downlink SharedChannel (PDSCH)/PDCCH/enhanced PDCCH (EPDCCH), and a channel accessprocess (that is also called Cat 2 channel access) that needs to senddiscovery reference signals. Similarly, these two channel accessprocesses are also supported in LAA uplink transmission, which arecalled Type 1 channel access and Type 2 channel access. Type 1 channelaccess is based on Cat 4 channel access, and Type 2 channel access isbased on a fixed time length (Cat 2) channel access which has at least25 us of LBT before transmission.

Type 1: a channel is detected to determine if it is in an idle stateduring a defer duration T_(d), the value of N in Step 4 is 0, and Nincreases with a sensing slot duration. Steps in Type 1 channel accessprocess are described as follows.

Step 1: set N=N_(init), where N_(init) is a random number uniformlydistributed between 0 and CW_(p), and go to step 4.

Step 2: if N>0 and eNB/gNB chooses to decrement a counter, set N=N−1.

Step 3: sense the channel for an additional sensing slot duration, andif the additional sensing slot duration is idle, go to step 4;otherwise, go to step 5.

Step 4: if N=0, stop; otherwise, go to Step 2.

Step 5: sense the channel for an additional defer duration T_(d) untileither a busy sensing slot is detected within the additional deferduration T_(d) or all sensing slots of the additional defer durationT_(d) are detected to be idle.

Step 6: if the channel is sensed to be idle during all the sensing slotdurations of the additional defer duration T_(d), go to step 4;otherwise, go to step 5.

In the channel access process described above, different Maximum ChannelOccupy Time (MCOT) is required according to different channel accesspriorities. The MCOT which means a maximum available time period of thechannel, is shown as T_(mcot,p) in Table 2.

TABLE 2 Channel Access allowed Priority CW_(p) Class (p) m_(p)CW_(min, p) CW_(max, p) T_(mcot, p) sizes 1 1 3 7 2 ms {3, 7} 2 1 7 15 3ms  {7, 15} 3 3 15 63 8 or 10 ms {15, 31, 63} 4 7 1 1023 8 or 10 ms {15,31, 63, 127, 255, 511, 1023}

Type 2: if the channel is detected for at least T_(drs)=25 us, averageenergy is lower X_(Thresh), and transmission time is less than 1 ms,downlink or uplink data can be sent on a channel transmitted by anunauthorized cell.

The two processes described above may be referred to as channel accessType 1 and Type 2 hereinafter.

In an unlicensed spectrum, after finishing LBT and accessing a channelsuccessfully, a base station cannot notify a UE of the channeloccupation situation, thus it cannot share the channel with the UEeffectively.

SUMMARY

Embodiments of the present disclosure provide a method and a device fornotifying channel occupation time, a base station and a user equipment,wherein a time slot format information is sent through a PDCCH, so as tonotify a UE of the channel occupation situation, thereby sharing thechannel with the UE effectively and improving channel occupation rate.

In an embodiment of the present disclosure, a method for notifyingchannel occupation time is provided, wherein the method applies to abase station, including: in an unlicensed spectrum, performingListen-Before-Talk (LBT) and conducting channel access; and when achannel is accessed successfully, sending a time slot format informationwhich indicates one or more time slots of one or more cells to a UEthrough a PDCCH, so as to notify the UE that the base station accessesthe channel and occupies the channel.

In some embodiments, sending a time slot format information whichindicates one or more time slots of one or more cells to a UE through aPDCCH includes: sending the time slot format information which indicatesone or more time slots of one or more cells to the UE through DownlinkControl Information (DCI) 2-0 of the PDCCH.

In some embodiments, performing Listen-Before-Talk (LBT) and conductingchannel access includes: conducting channel access according to Type 1.

In some embodiments, if a transmission period of the PDCCH or anabsolute time corresponding to a number of time slot formats indicatinga corresponding cell in the PDCCH is less than or equal to a currentmaximum channel occupation time, all the time slot format information inthe PDCCH is channel occupation information.

In some embodiments, if the transmission period of the PDCCH or theabsolute time corresponding to the number of time slot formatsindicating a corresponding cell in the PDCCH is greater than the currentmaximum channel occupation time, the time slot format information in thePDCCH includes channel occupation information and channel releaseinformation.

In some embodiments, the channel occupation information includes: whenan absolute time corresponding to a number of all time slot formatsindicating a corresponding cell in the PDCCH is less than or equal tothe maximum channel occupation time, or an absolute time correspondingto a number of partial time slot formats indicating a corresponding cellis less than or equal to the maximum channel occupation time, using aspecific time slot format to indicate it is within the maximum channeloccupation time or channel occupation.

In some embodiments, using a specific time slot format to indicate it iswithin the maximum channel occupation time or channel occupationincludes: using all D to indicate that the channel is occupied in anentire time slot, the base station sends downlink data in the entiretime slot, and the UE needs to receive; using all U to indicate that thechannel is occupied in the entire time slot and the UE can send uplinkdata in the entire time slot; in a switching point, using D+X+U or X+Uto indicate that the channel is occupied in the entire time slot,wherein the UE can send uplink data on an UL symbol, send downlink dataon a DL symbol, and perform channel access on an X symbol; and in twoswitching points, indicating that the channel is occupied in the entiretime slot, wherein the UE can send uplink data on an UL symbol, senddownlink data on a DL symbol, and perform channel access on an X symbol.

In some embodiments, the channel release information includes: when alength forma of the absolute time corresponding to the number of timeslot formats in the PDCCH indicating a corresponding cell exceeds themaximum channel occupation time, using a specific time slot format toindicate that the maximum channel occupation tine is exceeded or channelrelease.

In some embodiments, using a specific time slot format to indicate thatthe maximum channel occupation time is exceeded or channel releaseincludes: using all X to indicate that the maximum channel occupationtime is exceeded or channel release in the entire time slot; using DL+Xto indicate that the maximum channel occupation time is exceeded orchannel release in some time slots; and using all X to indicate that acorresponding cell has not been accessed successfully or the channel isreleased.

In an embodiment of the present disclosure, a method for notifyingchannel occupation time is provided, wherein the method applies to auser equipment, including: in an unlicensed spectrum, receiving a timeslot format information sent by a base station through a PDCCH after thebase station accesses a channel successfully, wherein the time slotformat information indicates one or more time slots of one or morecells; according to the slot format information, acquiring channeloccupation information and channel release information; and according tothe channel occupation information and the channel release information,performing downlink reception, uplink transmission or channel access insymbols of each time slot.

In some embodiments, according to the slot format information, acquiringchannel occupation information and channel release information includes:acquiring at least one of the following information: whether the basestation accesses the channel successfully or not, a length of channeloccupation time, a timing for channel release, and an allocationinformation of downlink symbols and uplink symbols in each time slotduring the channel occupation time.

In some embodiments, according to the channel occupation information andthe channel release information, performing downlink reception, uplinktransmission or channel access in symbols of each time slot includes:receiving a downlink signal or channel in the downlink symbolsindicating time slot format.

In some embodiments, according to the channel occupation information andthe channel release information, performing downlink reception, uplinktransmission or channel access in symbols of each time slot includes: inthe uplink symbols indicating time slot format, performing channelaccess according to Type 2 channel access process, or sending an uplinkchannel or signal directly without performing LBT.

In some embodiments, according to the channel occupation information andthe channel release information, performing downlink reception, uplinktransmission or channel access in symbols of each time slot includes: inthe uplink symbols and flexible symbols indicating time slot format,performing channel access according to Type 2 channel access process, orsending a dynamic uplink channel or signal triggered by a physical layersignaling directly without performing LBT.

In an embodiment of the present disclosure, a device for notifyingchannel occupation time is provided, wherein the device is located at abase station, including: an access unit, configured to perform LBT andconduct channel access in an unlicensed spectrum; and a transmissionunit, when a channel is accessed successfully, configured to send a slotformat information which indicates one or more time slots of one or morecells to a UE through a PDCCH, so as to notify the UE that the basestation accesses the channel and occupies the channel.

In some embodiments, the transmission unit is configured to send theslot format information which indicates one or more time slots of one ormore cells to the UE through DCI 2-0 of the PDCCH.

In some embodiments, the access unit performs channel access accordingto Type 1.

In some embodiments, if a transmission period of the PDCCH or anabsolute time corresponding to a number of time slot formats indicatinga corresponding cell in the PDCCH is less than or equal to a currentmaximum channel occupation time, all the time slot format information inthe PDCCH is channel occupation information.

In some embodiments, if the transmission period of the PDCCH or theabsolute time corresponding to the number of time slot formatsindicating a corresponding cell in the PDCCH is greater than the currentmaximum channel occupation time, the time slot format information in thePDCCH includes channel occupation information and channel releaseinformation.

In some embodiments, the channel occupation information includes: whenan absolute time corresponding to a number of all time slot formatsindicating a corresponding cell in the PDCCH is less than or equal tothe maximum channel occupation time, or an absolute time correspondingto a number of partial time slot formats indicating a corresponding cellis less than or equal to the maximum channel occupation time, using aspecific time slot format to indicate it is within the maximum channeloccupation time or channel occupation.

In some embodiments, using a specific time slot format to indicate it iswithin the maximum channel occupation time or channel occupationincludes: using all D to indicate that the channel is occupied in anentire time slot, the base station sends downlink data in the entiretime slot, and the UE needs to receive; using all U to indicate that thechannel is occupied in the entire time slot and the UE can send uplinkdata in the entire time slot; in a switching point, using D+X+U or X+Uto indicate that the channel is occupied in the entire time slot,wherein the UE can send uplink data on an UL symbol, send downlink dataon a DL symbol, and perform channel access on an X symbol; and in twoswitching points, indicating that the channel is occupied in the entireslot, wherein the UE can send uplink data on an UL symbol, send downlinkdata on a DL symbol, and perform channel access on an X symbol.

In some embodiments, the channel release information includes: when alength of the absolute time corresponding to the number of time slotformats in the PDCCH indicating corresponding cell exceeds the maximumchannel occupation time, using a specific time slot format to indicatethat the maximum channel occupation time is exceeded or channel release.

In some embodiments, using a specific time slot format to indicate thatthe maximum channel occupation time is exceeded or channel releaseincludes: using all X to indicate that the maximum channel occupationtime is exceeded or channel release in the entire time slot; using DL+Xto indicate that the maximum channel occupation time is exceeded orchannel release in some time slots; and using all X to indicate that acorresponding cell has not been accessed successfully or the channel isreleased.

In an embodiment of the present disclosure, a device for notifyingchannel occupation time is provided, wherein the device is located at auser equipment, including: a reception unit, configured to receive aslot format information which is sent by a base station through a PDCCHafter accessing a channel successfully in an unlicensed spectrum,wherein the slot format information indicates one or more time slots ofone or more cells; an acquiring unit, configured to acquire channeloccupation information and channel release information according to thetime slot format information; and a processing unit, configured toperform downlink reception, uplink transmission or channel access insymbols of each time slot, according to the channel occupationinformation and the channel release information.

In some embodiments, the acquiring unit acquires at least one of thefollowing information: whether the base station accesses the channelsuccessfully or not, a length of channel occupation time, a timing forchannel release, and an allocation information of downlink symbols anduplink symbols in each time slot during the channel occupation time.

In some embodiments, the processing unit receives a downlink signal orchannel in the downlink symbols indicating time slot format.

In some embodiments, in the uplink symbols indicating time slot format,the processing unit performs channel access according to Type 2 channelaccess process, or sends an uplink channel or signal directly withoutperforming LBT.

In some embodiments, in the uplink symbols and flexible symbolsindicating time slot format, the processing unit performs channel accessaccording to Type 2 channel access process, or sends a dynamic uplinkchannel or signal triggered by a physical layer signaling directlywithout performing LBT.

In an embodiment of the present disclosure, a base station having adevice for notifying channel occupation time described above isprovided, wherein the device is located at the base station.

In an embodiment of the present disclosure, a user equipment having adevice for notifying channel occupation time described above isprovided, wherein the device is located at the user equipment.

According to embodiments of the present disclosure described above, amethod and a device for notifying channel occupation time, a basestation and a user equipment are provided. After accessing a channelsuccessfully, the base station sends a time slot format informationthrough a PDCCH to the UE, so as to notify the UE of the channeloccupation situation, thereby sharing the channel with the UEeffectively and improving channel occupation rate and systemperformance.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 to 5 are exemplary settings of 14 symbols in a time slotaccording to prior art;

FIG. 6 schematically illustrates a flow chart of a method for notifyingchannel occupation time according to an embodiment;

FIG. 7 schematically illustrates a flow chart of a method for notifyingchannel occupation time according to another embodiment;

FIG. 8 schematically illustrates a structural diagram of a device fornotifying channel occupation time according to an embodiment; and

FIG. 9 schematically illustrates a structural diagram of a device fornotifying channel occupation time according to another embodiment.

DETAILED DESCRIPTION

To make the objectives, technical solutions, and advantages of theembodiments of the present invention clearer, the following clearlydescribes the technical solutions in the embodiments of the presentinvention with reference to the accompanying drawings in the embodimentsof the present invention. Apparently, the described embodiments are somebut not all of the embodiments of the present invention. All otherembodiments obtained by persons of ordinary skill in the art based onthe embodiments of the present invention without creative efforts shallbe within the protection scope of the present invention.

Embodiments of the present disclosure provide a method for notifyingchannel occupation time, wherein the method applies to a base station.Referring to FIG. 6 , the method includes S11 and S12.

S11: in an unlicensed spectrum, the base station performsListen-Before-Talk (LBT) and conducts channel access.

First, a search space carrying DCI 2-0 in a PDCCH is sent according to ahigh-level signaling configuration, which includes a transmission periodand an offset. A UE periodically monitors the PDCCH according to theconfiguration. the DCI 2-0 may include time slot formats of multipleslots of multiple cells, wherein a number of cells and a number of slotsin each cell are configured by the high-level signaling.

S12: when a channel is accessed successfully, the base station sends atime slot format information which indicates one or more time slots ofone or more cells to the UE through the PDCCH, so as to notify the UEthat the base station accesses the channel and occupies the channel.

Specifically, the base station sends the time slot format informationwhich indicates one or more time slots of one or more cells to the UEthrough DCI 2-0 of the PDCCH.

According to the embodiment of the present disclosure described above, amethod for notifying channel occupation time is provided. The basestation sends the time slot format information through the PDCCH to theUE, so as to notify the UE of the channel occupation situation.Therefore, after accessing the channel successfully, the base stationcan share the channel with the UE effectively, thereby improving channeloccupation rate and system performance.

In some embodiments, only after a gNB access the channel according toType 1, it can send the time slot format information which indicates oneor more time slots of one or more cells to the UE.

When the gNB uses a Type 1 channel to access one serving cell or aplurality of serving cells, duration of Maximum Channel Occupy Time(MCOT) is determined according to channel access priority class, andtransmission period of the PDCCH is configured semi-statically.

In some embodiments, if the transmission period of the PDCCH or anabsolute time corresponding to a number of time slot formats indicatinga corresponding cell in the PDCCH is less than or equal to a currentMCOT, all the time slot format information in the PDCCH is channeloccupation information.

In some embodiments, if the transmission period of the PDCCH or theabsolute time corresponding to the number of time slot formatsindicating a corresponding cell in the PDCCH is greater than the currentMCOT, the time slot format information in the PDCCH includes channeloccupation information and channel release information.

In some embodiments, the channel occupation information includes: whenan absolute time corresponding to a number of all time slot formatsindicating a corresponding cell in the PDCCH is less than or equal tothe MCOT, or an absolute time corresponding to a number of partial timeslot formats indicating a corresponding cell is less than or equal tothe MCOT, using a specific time slot format to indicate it is within themaximum channel occupation time or channel occupation.

In some embodiments, all D (format 0 in Table 1) is used to indicatethat the channel is occupied in an entire time slot, the gNB sendsdownlink data in the entire time slot, and the UE needs to receive; allU (format 1 in Table 1) is used to indicate that the channel is occupiedin the entire time slot and the UE can send uplink data in the entiretime slot; in a switching point, D+X+U (format 19-45 in Table 1) or X+U(format 8-15 in Table 1) is used to indicate that the channel isoccupied in the entire time slot, wherein the UE can send uplink data onan UL symbol, send downlink data on a DL symbol, and perform channelaccess on an X symbol; and in two switching points (format 46-55 inTable 1), it is indicated that the channel is occupied in the entiretime slot, wherein the UE can send uplink data on an UL symbol, senddownlink data on a DL symbol, and perform channel access on an X symbol.

In some embodiments, the channel release information includes: when alength of the absolute time corresponding to the number of time slotformats in the PDCCH indicating a corresponding cell exceeds the maximumchannel occupation time, using a specific time slot format to indicatethat the MCOT is exceeded or channel release.

In some embodiments, all X (format 2 in Table 1) is used to indicatethat the MCOT is exceeded or channel release in the entire time slot;and DL+X (format 3-7, 16, 17 and 18 in Table 1) is used to indicate thatthe MCOT is exceeded or channel release in some time slots.

When the time slot format of the PDCCH indicates a plurality of servingcells, if some of the serving cells are not accessed successfully, aspecific time slot format is used to indicate no channel occupation, theMCOT is exceeded, or channel release. Specifically, all X (format 2 inTable 1) is used to indicate that a corresponding serving cell has notbeen accessed successfully or the channel is released.

In an embodiment of the present disclosure, a method for notifyingchannel occupation time is provided, wherein the method applies to auser equipment,. Referring to FIG. 7 , the method includes S21, S22 andS23.

S21: in an unlicensed spectrum, the UE receives a time slot formatinformation sent by a base station through a PDCCH after the basestation accesses a channel successfully, wherein the time slot formatinformation indicates one or more time slots of one or more cells.

Specifically, the UE receives the time slot format information sent bythe base station through DCI 2-0 of the PDCCH, wherein the time slotformat information indicates one or more time slots of one or morecells.

S22: according to the slot format information, the UE acquires channeloccupation information and channel release information.

Specifically, after receiving the DCI 2-0 of the PDCCH, the UE acquiresthe channel occupation information and the channel release informationaccording to the slot format information and acquires at least one ofthe following information: whether the gNB accesses the channelsuccessfully or not, a length of channel occupation time, a timing forchannel release, and an allocation information of downlink symbols anduplink symbols in each time slot during the channel occupation time.

S23: according to the channel occupation information and the channelrelease information, the UE performs downlink reception, uplinktransmission or channel access in symbols of each time slot.

According to the embodiment of the present disclosure described above, amethod for notifying channel occupation time is provided. Afteraccessing the channel successfully, the base station sends the time slotformat information through the PDCCH to the UE, so as to notify the UEthe channel occupation information and the channel release information.According to the channel occupation information and the channel releaseinformation, the UE performs downlink reception, uplink transmission orchannel access in symbols of each time slot, thereby sharing the channelwith the UE effectively and improving channel occupation rate and systemperformance.

In some embodiments, according to the channel occupation information andthe channel release information, the UE performing downlink reception,uplink transmission or channel access in symbols of each time slotincludes: in the downlink symbols indicating time slot format, the UEreceives a downlink signal or channel; in the uplink symbols indicatingthe slot format, the UE performs channel access according to Type 2channel access process (short LBT), or sending an uplink channel orsignal directly without performing LBT, wherein the uplink channel orsignal may be a periodic signal, such as a periodic Sounding ReferenceSignal (SRS), a Physical Uplink Control Channel (PUCCH), a configureduplink authorized transmission, or it may also be an uplink channelconfigured by a high-level signaling, such as a Physical Random-AccessChannel (PRACH); and in the uplink symbols and flexible symbolsindicating the slot format, the UE performs channel access according toType 2 channel access process (short LBT), or sending a dynamic uplinkchannel or signal triggered by a physical layer signaling directlywithout performing LBT, for example, a nonperiodic SRS, a dynamicPhysical Uplink Shared Channel (PUSCH).

In an embodiment of the present disclosure, a device for notifyingchannel occupation time is provided, wherein the device is located at abase station. Referring to FIG. 8 , the device includes:

an access unit 11, configured to perform LBT and conduct channel accessin an unlicensed spectrum; and

a transmission unit 12, when a channel is accessed successfully,configured to send a slot format information which indicates one or moretime slots of one or more cells to a UE through a PDCCH, so as to notifythe UE that the base station accesses the channel and occupies thechannel.

According to the embodiment of the present disclosure described above, adevice for notifying channel occupation time is provided. The basestation sends the time slot format information through the PDCCH to theUE, so as to notify the UE of the channel occupation situation.Therefore, after accessing the channel successfully, the base stationcan share the channel with the UE effectively, thereby improving channeloccupation rate and system performance.

In some embodiments, the transmission unit 12 is configured to send theslot format information which indicates one or more time slots of one ormore cells to the UE through DCI 2-0 of the PDCCH.

In some embodiments, the access unit 11 performs channel accessaccording to Type 1.

In some embodiments, if a transmission period of the PDCCH or anabsolute time corresponding to a number of time slot formats indicatinga cone ding cell in the PDCCH is less than or equal to a current maximumchannel occupation time, all the time slot format information in thePDCCH is channel occupation information.

In some embodiments if the transmission period of the PDCCH or theabsolute time corresponding to the number of time slot formatsindicating a corresponding cell in the PDCCH is greater than the currentmaximum channel occupation time, the time slot format information in thePDCCH includes channel occupation information and channel releaseinformation.

In some embodiments, the channel occupation information includes: whenan absolute time corresponding to a number of all time slot formatsindicating a corresponding cell in the PDCCH is less than or equal tothe maximum channel occupation time, or an absolute time correspondingto a number of partial time slot formats indicating a corresponding cellis less than or equal to the maximum channel occupation time, using aspecific time slot format to indicate it is within the maximum channeloccupation time or channel occupation.

In some embodiments, using a specific time slot format to indicate it iswithin the maximum channel occupation time or channel occupationincludes: using all D to indicate that the channel is occupied in anentire time slot, the base station sends downlink data in the entiretime slot, and the UE needs to receive; using all U to indicate that thechannel is occupied in the entire time slot and the UE can send uplinkdata in the entire time slot; in a switching point, using D+X+U or X+Uto indicate that the channel is occupied in the entire time slot,wherein the UE can send uplink data on an UL symbol, send downlink dataon a DL symbol, and perform channel access on an X symbol; and in twoswitching points, indicating that the channel is occupied in the entiretime slot, wherein the UE can send uplink data on an UL symbol, senddownlink data on a DL symbol, and perform channel access on an X symbol.

In some embodiments, the channel release information includes: when alength of the absolute time corresponding to the number of time slotformats in the PDCCH indicating a corresponding cell exceeds the maximumchannel occupation time, using a specific time slot format to indicatethat the maximum channel occupation time is exceeded or channel release.

In some embodiments, using a specific time slot format to indicate thatthe maximum channel occupation time is exceeded or channel releaseincludes: using all X to indicate that the maximum channel occupationtime is exceeded or channel release in the entire time slot; using DL+Xto indicate that the maximum channel occupation time is exceeded orchannel release in some time slots; and using all X to indicate that acorresponding cell has not been accessed successfully or the channel isreleased.

The device provided in the embodiments described above can be used toexecute the technical solutions provided in the above method embodimentswhich applies to a base station. The implementation principles andtechnical effects are similar, which will not be described in detailherein again.

In an embodiment of the present disclosure, a device for notifyingchannel occupation time is provided, wherein the device is located at auser equipment. Referring to FIG. 9 , the device includes:

a reception unit 21, configured to receive a slot format informationwhich is sent by a base station through a PDCCH after accessing achannel successfully in an unlicensed spectrum, wherein the slot formatinformation indicates one or more time slots of one or more cells;

an acquiring unit 22, configured to acquire channel occupationinformation and channel release information according to the time slotformat information; and

a processing unit 23, configured to perform downlink reception, uplinktransmission or channel access in symbols of each time slot, accordingto the channel occupation information and the channel releaseinformation.

According to the embodiment of the present disclosure described above, adevice for notifying channel occupation time is provided. Afteraccessing the channel successfully, the base station sends the time slotformat information through the PDCCH to the UE, so as to notify the UEthe channel occupation information and the channel release information.According to the channel occupation information and the channel releaseinformation, the UE performs downlink reception, uplink transmission orchannel access in symbols of each time slot, thereby sharing the channelwith the UE effectively and improving channel occupation rate and systemperformance.

In some embodiments, the acquiring unit 22 acquires at least one of thefollowing information: whether the base station accesses the channelsuccessfully or not, a length of channel occupation time, a timing forchannel release, and an allocation information of downlink symbols anduplink symbols in each time slot during the channel occupation time.

In some embodiments, the processing unit 23 receives a downlink signalor channel in the downlink symbols indicating time slot format.

In some embodiments, in the uplink symbols indicating the slot format,the processing unit 23 performs channel access according to Type channelaccess process, or sends an uplink channel or signal directly withoutperforming LBT.

In some embodiments, in the uplink symbols and flexible symbolsindicating the slot format, the processing unit 23 performs channelaccess according to Type 2 channel access process, or sends a dynamicuplink channel or signal triggered by a physical layer signalingdirectly without performing LBT.

The device provided in the embodiments described above can be used toexecute the technical solutions provided in the above method embodimentswhich applies to a user equipment. The implementation principles andtechnical effects are similar, which will not be described in detailherein again.

In an embodiment of the present disclosure, a base station having adevice for notifying channel occupation time described above isprovided, wherein the device is located at the base station.

In an embodiment of the present disclosure, a user equipment having adevice for notifying channel occupation time described above isprovided, wherein the device is located at the user equipment.

Those skilled in the art can understand that a part or all of themethods described in the embodiments of the present disclosure can beperformed by a computer program instructing a related hardware. Thecomputer program can be stored in a computer-readable storage medium,and when the computer program is executed, the computer program caninclude processes of the foregoing methods described in the embodiment.The storage medium may be a magnetic disk, an optical disk, a Read-OnlyMemory (ROM), or a Random Access Memory (RAM), etc.

Although the present disclosure has been disclosed above with referenceto preferred embodiments thereof, it should be understood that thedisclosure is presented by way of example only, and not limitation.Those skilled in the art can modify and vary the embodiments withoutdeparting from the spirit and scope of the present disclosure.

What is claimed is:
 1. A method for notifying channel occupation time,comprising: receiving, by a User equipment (UE), Downlink ControlInformation (DCI) 2-0 through Physical Downlink Control Channel (PDCCH),wherein the DCI 2-0 comprises time slot format information, and the timeslot format information indicates one or more time slots of one or morecells; acquiring, by the UE, a length of channel occupation time and anallocation information of downlink symbols, uplink symbols and flexiblesymbols in each time slot during the channel occupation time based onthe DCI 2-0; and performing downlink reception, uplink transmission orchannel access, by the UE, in symbols of each time slot based on theallocation information.
 2. The method according to claim 1, wherein saidperforming downlink reception, uplink transmission or channel access insymbols of each time slot based on the allocation information comprises:in the uplink symbols of time slots, performing channel access accordingto Type 2 channel access process.
 3. The method according to claim 1,wherein said performing downlink reception, uplink transmission orchannel access in symbols of each time slot based on the allocationinformation comprises: in the uplink symbols of time slots, sending anuplink channel or signal directly without performing Listen-Before-Talk(LBT).
 4. The method according to claim 1, wherein said performingdownlink reception, uplink transmission or channel access in symbols ofeach time slot based on the allocation information comprises: in thedownlink symbols of time slots, receiving a downlink signal or channel.5. The method according to claim 1, wherein said performing downlinkreception, uplink transmission or channel access in symbols of each timeslot based on the allocation information comprises: in uplink symbolsand flexible symbols of time slots, performing channel access accordingto Type 2 channel access process.
 6. The method according to claim 1,wherein said performing downlink reception, uplink transmission orchannel access in symbols of each time slot based on the allocationinformation comprises: in uplink symbols and flexible symbols of timeslots, sending an uplink channel or signal directly without performingLBT.
 7. A method for notifying channel occupation time, comprising:performing, by a base station, access process; and sending, by the basestation, Downlink Control Information (DCI) 2-0 through PhysicalDownlink Control Channel (PDCCH), wherein the DCI comprises time slotformat information, and the time slot format information indicates oneor more time slots of one or more cells, wherein the DCI 2-0 is used fora UE to acquire a length of channel occupation time and an allocationinformation of downlink symbols, uplink symbols and flexible symbols ineach time slot during the channel occupation time based on the time slotformat information and perform downlink reception, uplink transmissionor channel access in symbols of each time slot based on the allocationinformation.
 8. The method according to claim 7, wherein the DCI 2-0 isused for the UE to: perform channel access according to Type 2 channelaccess process in the uplink symbols of time slots.
 9. The methodaccording to claim 7, wherein the DCI 2-0 is used for the UE to: send anuplink channel or signal directly without performing Listen-Before-Talk(LBT) in the uplink symbols of time slots.
 10. The method according toclaim 7, wherein the DCI 2-0 is used for the UE to: receive a downlinksignal or channel in the downlink symbols of time slots.
 11. The methodaccording to claim 7, wherein the DCI 2-0 is used for the UE to: performchannel access according to Type 2 channel access process in uplinksymbols and flexible symbols of each time slots.
 12. The methodaccording to claim 7, wherein the DCI 2-0 is used for the UE to: send anuplink channel or signal directly without performing LBT in uplinksymbols and flexible symbols of each time slots.
 13. A user equipmentfor notifying channel occupation time, comprising a device configuredto: receive Downlink Control Information (DCI) 2-0 through PhysicalDownlink Control Channel (PDCCH), wherein the DCI 2-0 comprises timeslot format information, and the time slot format information indicatesone or more time slots of one or more cells; acquire a length of channeloccupation time and an allocation information of downlink symbols,uplink symbols and flexible symbols in each time slot during the channeloccupation time based on the DCI 2-0; and perform downlink reception,uplink transmission or channel access in symbols of each time slot basedon the allocation information.
 14. The user equipment according to theclaim 13, wherein the device further is configured to: in the uplinksymbols of time slots, perform channel access according to Type 2channel access process.
 15. The user equipment according to the claim13, wherein the device further is configured to: send an uplink channelor signal directly without performing Listen-Before-Talk (LBT) in theuplink symbols of time slots.
 16. The user equipment according to theclaim 13, wherein the device further is configured to: send an uplinkchannel or signal directly without performing LBT in the uplink symbolsof time slots.
 17. The user equipment according to the claim 13, whereinthe device further is configured to: perform channel access according toType 2 channel access process in uplink symbols and flexible symbols ofeach time slots.
 18. The user equipment according to the claim 11,wherein the device further is configured to: send an uplink channel orsignal directly without performing LBT in uplink symbols and flexiblesymbols of each time slots.